This invention relates to a plant for the production of popsicles and icecreams incorporating a holding stick.
As is known, many icecreams and most popsicles are produced commercially on special plants of either circular or linear types wherethrough dies or patterns or molds holding the icecreams are made to advance. The molds are moved past a number of processing stations, such as dispensing stations whereat the liquids to be frozen are poured out, stick-applying stations, and shake-out stations for the molded icecreams or popsicles. In their movement past these stations, the molds are kept immersed in special refrigerating liquids contained in long vats which are raised to nearly level with the mold top openings.
Such plants have important deficiencies.
A first problem originates from the overall construction of the plants themselves, which are to convey the molds along closed paths for obvious practical and functional reasons. The closed paths may be circular and define a flat loop, or be substantially linear and define two main linear sections, a forward one and return one, superimposed on each other.
In the former case, the whole plant is potentially usable, and a processing station or a cooling section can be provided anywhere therethrough. However, the circular pattern is highly demanding on floor area, and makes the processing station layout difficult. In fact, if the stations are arranged on the inside of the loop structure, they are left with little available room, whereas if they are placed on the outside, access to the work area may become difficult. Furthermore, some dies or molds (the outermost ones) describe much longer paths than other dies or molds (the innermost ones). The outermost molds are, therefore, subjected to a more intense heat exchange with the refrigerating liquid. It should be noted, finally, that the molds must be arranged in groups on segmented rigid plates, and that for advancing such segmented plates special measures have to be taken, which increases costs.
The linearly extending plants, with two superimposed sections, are advantageous in that they fit more easily in the spaces available to production and in that the processing station layout is made easier. Accessibility to the work area is also quite satisfactory, and the dies or molds can be grouped over rigid plates of very simple, typically rectangular, design. With these plants, cooling is uniform for all the molds because these travel along equal paths.
On the other hand, linear plants have a bottom return run for the dies or molds which is left unused. Also the connecting portions, of semicircular shape, of the path for the molds are practically unusable.
The situation is further burdened by that along the bottom return run, the dies or molds are turned over and at ambient temperature. It follows that an amount of the icecream is lost, that is all the icecream which has not been removed at the end of the top run, and that the dies or molds become liable to contamination by the environment outside the plant. Contamination affects in particular the thawing residue of unextracted icecream. This situation actually dictates a mold flushing operation while they travel along the bottom run of their path.
A second problem of plants producing popsicles and icecreams incorporating a holding stick comes from the type of cooling universally adopted for such plants: cooling is provided by refrigerating liquids whereinto the molds to be cooled are substantially immersed.
The use of refrigerating liquids involves the provision of special channels therefor, special devices to circulate the liquids through said channels, and periodic cleaning operations which are complicated and expensive to carry out because they require that the cited channels be emptied.
Furthermore, the so-called "brine" is used normally as the refrigerating liquid, which comprises a calcium chloride solution. This brine has the specific disadvantage of contaminating and significantly corroding all the elements which are put in contact with it. Thus, all the equipment must be overhauled and replaced with some frequency, and the operators also feel the effects of the pollution brought about by the presence of said calcium chloride solution. There still exists, moreover, the potential hazard of contaminating the food products in the event of a malfunction of the devices that control the brine flow.
It is known to use refrigerating liquids other than said brine and such as to be potentially non-polluting and non-corrosive. However, the cost of such alternative liquids is high and not always acceptable.
It should be noted that prior plants employ liquids not only to refrigerate the dies or molds but also to heat the mold exteriors after they have been refrigerated, in order to favor withdrawal of the finished icecreams or popsicles. For example, hot water is used which is made to contact the molds on their leaving the cited brine by means of movable trays in the vertical direction on control by specially provided mechanisms. The latter further aggravate costs and the complexity of prior plants.